Real time method of detecting acute inflammatory conditions

Abstract

This invention relates to the diagnosis and/or monitoring of patients with inflammatory diseases or conditions, including systemic lupus erythematosus, particularly for diagnosis of the acute stage of the disease, including methods and kits for carrying out this activity. This disclosure presents the surprising discovery that levels of complement pathway components on reticulocytes can be used to diagnose, monitor, or predict the occurrence of acute episodes of chronic inflammatory diseases or conditions.

1. A method for diagnosing an acute inflammatory episode of systemic lupus erythematosus (SLE) in an individual, the method comprising:
 (a) isolating reticulocytes from a blood sample of an individual; 
 (b) determining the level of a C4d complement pathway component on the isolated reticulocytes from the individual, and 
 (c) comparing the C4d complement pathway component level on the isolated reticulocytes from the individual with a control level of C4d complement pathway component on reticulocytes, wherein an elevated level of the C4d complement pathway component on the isolated reticulocytes in the individual compared to the control level of the C4d complement pathway component on reticulocytes indicates that the individual has the acute inflammatory episode of SLE. 
 
     
     
       2. The method of  claim 1 , wherein the level of the C4d complement pathway component is determined using an antibody specific for the C4d complement pathway component. 
     
     
       3. The method of  claim 2 , wherein the C4d antibody is labeled. 
     
     
       4. The method of  claim 3 , wherein the C4d antibody is detected using flow cytometric analysis. 
     
     
       5. A method of predicting an acute inflammatory episode of systemic lupus erythematosus (SLE) in an individual, the method comprising:
 (a) isolating reticulocytes from a blood sample of an individual; 
 (b) determining the level of a C4d complement pathway component on the isolated reticulocytes from the individual, and 
 (c) comparing the C4d complement pathway component level on the isolated reticulocytes from the individual with a control level of complement pathway component on reticulocytes, wherein an elevated level of the C4d complement pathway component in the isolated reticulocytes in the individual compared to the control level of the C4d complement pathway component on reticulocytes is predictive of an acute inflammatory episode of SLE. 
 
     
     
       6. The method of  claim 5 , wherein the level of the C4d complement pathway component is determined using an antibody specific for the C4d complement pathway component. 
     
     
       7. The method of  claim 6 , wherein the C4d antibody is labeled. 
     
     
       8. The method of  claim 7 , wherein the C4d antibody is detected using flow cytometric analysis. 
     
     
       9. A method for monitoring the clinical course of an acute inflammatory episode of systemic lupus erythematosus (SLE), the method comprising:
 (a) isolating reticulocytes from a blood sample of an individual at a first time point and at a second time point; 
 (b) determining the level of a C4d complement pathway component on the isolated reticulocytes of the individual at the first time point; and 
 (c) comparing the level of the C4d complement pathway component on the isolated reticulocytes of the individual at the first time point with the isolated reticulocytes of the individual at the second time point, wherein a change in the level of the C4d complement pathway component on the isolated reticulocytes from the first time point to the second time point of the individual indicates a change in the clinical course of the acute inflammatory episode of SLE in the individual. 
 
     
     
       10. The method of  claim 9 , wherein the level of the C4d complement pathway component is determined using an antibody specific for the C4d complement pathway component. 
     
     
       11. The method of  claim 10 , wherein the C4d antibody is labeled. 
     
     
       12. The method of  claim 11 , wherein the C4d antibody is detected using flow cytometric analysis.